1. Field of the Invention
The present invention relates to an operation input device and a method of initializing the operation input device. The present invention relates to, for example, an operation input device that has a plurality of multi-jointed arms and performs an operation input by moving the plurality of multi-jointed arms, and a method of initializing the operation input device.
2. Description of Related Art
In the related art, in an apparatus (for example, a remote control robot, an operation input device for performing a surgical assistant of a surgical operation or the like) in which an actuating unit is held in a plurality of multi-jointed robots, there has been known a configuration that uses an operation input device including an multi-jointed arm having the same degree of freedom as that of the actuating unit, when performing the movement operation of the actuating unit. For example, in a medical manipulator system of a master-slave type, a master manipulator, which inputs the movement of the slave manipulator, constitutes such an operation input device.
Such the operation input device detects a rotation angle of the joint detected by each joint of the multi-jointed arm, the length of the arm between the joints or the like, and detects the position and the orientation of an operation unit provided on the multi-jointed arm corresponding to the actuating unit and transmits the detected data to a control device of the multi-jointed robot. The control device of the multi-jointed robot performs the control of driving the actuating unit in accordance with the position and the orientation that is transmitted from the operation input device.
The joint of the multi-jointed arm of the operation input device is equipped with a sensor that detects a rotation angle of the joint and a translation amount of the arm between the adjacent joints. However, in order to promote a low cost, in many cases, an encoder which cannot detect an absolute value is used.
In such an operation input device, in an initial state, a relationship between an output value of the encoder and the angle or the length of the joint is indefinite. For this reason, in order to perform the accurate operation input, there is a need for the initialization that performs an identification task between the output value of the encoder and the value of a physical joint angle or joint length.
For example, Published Japanese Translation No. 2007-510232 of the PCT International Publication discloses a force reflecting haptic interface that includes a docking station fixed to a base, and a rod-like user interface having a distal end capable of being held in a cylinder portion provided in the docking station.
In the force reflecting haptic interface, it is possible to set (initialize) a rest point and a home position of the distal end to a zero position or a user-designated home position, by holding the distal end of the user interface in the cylinder portion of the docking station of the fixed position.